As an example of procedures of manufacturing a semiconductor device, a procedure of forming a film such as a nitride film, an oxide film or the like on a substrate is often carried out by supplying, e.g., a precursor gas containing silicon and a reaction gas such as a nitriding gas, an oxidizing gas or the like to the substrate.
If carbon (C) or the like is added to the film formed on the substrate, it is possible to increase, e.g., a resistance to hydrogen fluoride (HF). If carbon is added to the film at a high concentration by accurately controlling a carbon concentration in the film, it is possible to further increase the HF resistance of the film.